Battery-operated energy supplies are generally used for supplying electronic circuits such as small radio transmitters, small sensors associated with radio transmitters, so-called radio sensors, radio switches or the like, which are often fitted to rotating elements for the purpose of monitoring or measuring a physical parameter. One disadvantage of the battery-operated energy supplies is the limited service life of the energy store battery which then needs to be replaced by a new battery or a new energy store. This requires a high degree of complexity in terms of maintenance and may lead to unnoticed failures of the electronic circuit in conjunction with the sensor and the devices also associated therewith.
Alternatively, energy converters are known, such as electromagnetic magnetostrictive or piezoelectric converters, which can also be implemented in a compact design and, inter alia, are suitable for converting movement energy into electrical energy, primarily in a sufficient amount.
Should such a sensor or energy supply for supplying such circuits be mounted on rotating elements, an additional problem arises in the case of these rotating elements. This problem arises as a result of the severe rotational centrifugal forces. These rotational centrifugal forces have the effect that the electrodynamic magnetostrictive or piezoelectric converter elements remain deflected owing to the rotational centrifugal forces and therefore can no longer contribute to the energy supply in this form. Very small manufacturing tolerances or assembly tolerances may further intensify this problem.